Uneven Floors, Cracks, Hollowing? Solve All Self-Leveling Issues in One Guide

 

1. Overview

Cement-based self-leveling is a dry-mix material made of special cement, fine aggregates, and polymer additives. When mixed with water, it produces a highly fluid slurry that levels itself by gravity, forming a smooth, strong, and even surface. It can serve as a substrate for wood flooring, tiles, carpets, or be used directly as a wear-resistant surface.

2. Key Features & Benefits

• High Fluidity: Self-leveling without heavy manual troweling.

• Fast Setting: Walkable in 4–6 hours, reducing project time.

• Excellent Flatness: ≤2mm deviation within 2m straightedge.

• High Strength: Superior compressive and flexural strength compared to traditional mortar.

• Thickness Range: Typically 2–10mm, adjustable by application.

• Seamless Finish: No joints, neat appearance, easy to clean.

3. Substrate Preparation

Substrate preparation is the key to final performance.

Requirements:

• Strength ≥20MPa, free of hollowing, dusting, or peeling.

• Moisture ≤6%; apply moisture barrier if needed.

• Clean surface without oil, dust, or coatings.

• High spots ground, cracks repaired.

Steps:

1. Hollowing repair: Remove weak spots and fill with repair mortar.

2. Crack treatment: Cut “V” grooves, fill with repair material.

3. Grinding & cleaning: Mechanical grinding and vacuuming.

4. Moisture-proofing: Apply barrier if required.

5. Primer coating: Apply 1–2 coats evenly, wait until fully dry.

4. Materials & Tools

Materials: Self-leveling dry mix, clean water, primer.
Tools: Electric mixer, mixing bucket, water container, notched trowel, spiked roller, laser level, spiked shoes, roller for primer.

5. Construction Process

1. Mixing: Add 6–6.5L water per 25kg powder; mix into uniform slurry.

2. Pouring & Spreading: Allow slurry to flow naturally, guide lightly if needed.

3. Defoaming: Wear spiked shoes, roll with spiked roller in cross directions.

4. Curing: Close the site for 24 hours; finish covering after 3–7 days.

6. Key Notes & Common Issues

• Environment: 5–35℃, RH <80%.

• Accurate water ratio: Too much reduces strength, too little lowers flowability.

• Use each batch within 20–30 minutes.

• Common issues: hollowing (weak substrate or poor primer), cracking (improper curing, untreated cracks), dusting (excess water or poor mixing).

7. Acceptance Criteria

• Surface: Smooth, uniform color, free of cracks, pinholes, or dusting.

• Flatness: ≤2mm deviation within 2m straightedge (≤1.5mm for high standard).

• Strength: 28-day compressive strength ≥20MPa (or product value).

• Hollowing test: No hollow sound when tapped.

Conclusion

Cement-based self-leveling is a “30% materials, 70% workmanship” technology. A successful project relies on proper substrate preparation, quality materials, standardized procedures, and careful curing. Professional installation is strongly recommended to achieve the best results.